Ethereum Eras
Ethereum's early history is organized into eras defined by major network upgrades. Each era brought new capabilities, fixed vulnerabilities, and shaped the smart contracts deployed during that period.
Frontier
The initial release of Ethereum. A bare-bones implementation for technical users.
2015-07-30 — 2016-03-14
Block 0 – 1,149,999
359 documented contracts
Homestead
The first planned hard fork. Removed the canary contract, adjusted gas costs.
2016-03-14 — 2016-07-20
Block 1,150,000 – 1,919,999
28 documented contracts
DAO Fork
The controversial fork to recover funds from The DAO hack.
2016-07-20 — 2016-10-18
Block 1,920,000 – 2,462,999
23 documented contracts
Tangerine Whistle
Emergency fork to address DoS attacks. Repriced IO-heavy opcodes.
2016-10-18 — 2016-11-22
Block 2,463,000 – 2,674,999
10 documented contracts
Spurious Dragon
Continued DoS protection. State trie clearing.
2016-11-22 — 2017-10-16
Block 2,675,000 – 4,369,999
100 documented contracts
Byzantium
First Metropolis hard fork. Added zk-SNARK precompiles, REVERT opcode, and staticcall.
2017-10-16 — 2019-02-28
Block 4,370,000 – 7,279,999
49 documented contracts
Constantinople
Second Metropolis hard fork. Added CREATE2, bitwise shifting opcodes, and cheaper SSTORE.
2019-02-28 — 2019-12-08
Block 7,280,000 – 9,068,999
1 documented contract